kernel/include/linux/nfs_fs.h, branch linux-3.17.y

NFS: allow lockless access to access_cache

2014-08-03T21:14:13Z

The access cache is used during RCU-walk path lookups, so it is best to avoid locking if possible as taking a lock kills concurrency. The rbtree is not rcu-safe and cannot easily be made so. Instead we simply check the last (i.e. most recent) entry on the LRU list. If this doesn't match, then we return -ECHILD and retry in lock/refcount mode. This requires freeing the nfs_access_entry struct with rcu, and requires using rcu access primatives when adding entries to the lru, and when examining the last entry. Calling put_rpccred before kfree_rcu looks a bit odd, but as put_rpccred already provides rcu protection, we know that the cred will not actually be freed until the next grace period, so any concurrent access will be safe. This patch provides about 5% performance improvement on a stat-heavy synthetic work load with 4 threads on a 2-core CPU. Signed-off-by: NeilBrown Signed-off-by: Trond Myklebust

NFS: teach nfs_neg_need_reval to understand LOOKUP_RCU

2014-08-03T21:14:12Z

This requires nfs_check_verifier to take an rcu_walk flag, and requires an rcu version of nfs_revalidate_inode which returns -ECHILD rather than making an RPC call. With this, nfs_lookup_revalidate can call nfs_neg_need_reval in RCU-walk mode. We can also move the LOOKUP_RCU check past the nfs_check_verifier() call in nfs_lookup_revalidate. If RCU_WALK prevents nfs_check_verifier or nfs_neg_need_reval from doing a full check, they return a status indicating that a revalidation is required. As this revalidation will not be possible in RCU_WALK mode, -ECHILD will ultimately be returned, which is the desired result. Signed-off-by: NeilBrown Signed-off-by: Trond Myklebust

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2014-06-12T17:30:18Z

Pull vfs updates from Al Viro: "This the bunch that sat in -next + lock_parent() fix. This is the minimal set; there's more pending stuff. In particular, I really hope to get acct.c fixes merged this cycle - we need that to deal sanely with delayed-mntput stuff. In the next pile, hopefully - that series is fairly short and localized (kernel/acct.c, fs/super.c and fs/namespace.c). In this pile: more iov_iter work. Most of prereqs for ->splice_write with sane locking order are there and Kent's dio rewrite would also fit nicely on top of this pile" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits) lock_parent: don't step on stale ->d_parent of all-but-freed one kill generic_file_splice_write() ceph: switch to iter_file_splice_write() shmem: switch to iter_file_splice_write() nfs: switch to iter_splice_write_file() fs/splice.c: remove unneeded exports ocfs2: switch to iter_file_splice_write() ->splice_write() via ->write_iter() bio_vec-backed iov_iter optimize copy_page_{to,from}_iter() bury generic_file_aio_{read,write} lustre: get rid of messing with iovecs ceph: switch to ->write_iter() ceph_sync_direct_write: stop poking into iov_iter guts ceph_sync_read: stop poking into iov_iter guts new helper: copy_page_from_iter() fuse: switch to ->write_iter() btrfs: switch to ->write_iter() ocfs2: switch to ->write_iter() xfs: switch to ->write_iter() ...

NFS: Create a common nfs_pgio_result_common function

2014-05-28T22:40:36Z

Combining these functions will let me make a single nfs_rw_common_ops struct (see the next patch). Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust

NFS: Create a common read and write data struct

2014-05-28T22:12:47Z

At this point, the only difference between nfs_read_data and nfs_write_data is the write verifier. Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust

convert the guts of nfs_direct_IO() to iov_iter

2014-05-06T21:32:44Z

Signed-off-by: Al Viro

pass iov_iter to ->direct_IO()

2014-05-06T21:32:44Z

unmodified, for now Signed-off-by: Al Viro

nfs: make nfs_async_rename non-static

2014-03-17T19:14:16Z

...and move the prototype for nfs_sillyrename to internal.h. Signed-off-by: Jeff Layton Tested-by: Anna Schumaker Signed-off-by: Trond Myklebust

NFS: Be more aggressive in using readdirplus for 'ls -l' situations

2014-02-11T19:01:20Z

Try to detect 'ls -l' by having nfs_getattr() look at whether or not there is an opendir() file descriptor for the parent directory. If so, then assume that we want to force use of readdirplus in order to avoid the multiple GETATTR calls over the wire. Signed-off-by: Trond Myklebust

Merge tag 'nfs-for-3.14-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2014-01-31T23:39:07Z

Pull NFS client bugfixes from Trond Myklebust: "Highlights: - Fix several races in nfs_revalidate_mapping - NFSv4.1 slot leakage in the pNFS files driver - Stable fix for a slot leak in nfs40_sequence_done - Don't reject NFSv4 servers that support ACLs with only ALLOW aces" * tag 'nfs-for-3.14-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: nfs: initialize the ACL support bits to zero. NFSv4.1: Cleanup NFSv4.1: Clean up nfs41_sequence_done NFSv4: Fix a slot leak in nfs40_sequence_done NFSv4.1 free slot before resending I/O to MDS nfs: add memory barriers around NFS_INO_INVALID_DATA and NFS_INO_INVALIDATING NFS: Fix races in nfs_revalidate_mapping sunrpc: turn warn_gssd() log message into a dprintk() NFS: fix the handling of NFS_INO_INVALID_DATA flag in nfs_revalidate_mapping nfs: handle servers that support only ALLOW ACE type.